hoarfrost
['hɒ:frɒst]
n. 白



hoarfrost
[ noun ]
ice crystals forming a white deposit (especially on objects outside)
<noun.substance>




Hoarfrost \Hoar"frost`\, n.
The white particles formed by the congelation of dew; white
frost. [Written also {horefrost}. See {Hoar}, a.]

He scattereth the hoarfrost like ashes. --Ps. cxlvii.
16.


Frost \Frost\ (fr[o^]st; 115), n. [OE. frost, forst, AS. forst,
frost. fr. fre['o]san to freeze; akin to D. varst, G., OHG.,
Icel., Dan., & Sw. frost. [root]18. See {Freeze}, v. i.]
1. The act of freezing; -- applied chiefly to the congelation
of water; congelation of fluids.

2. The state or temperature of the air which occasions
congelation, or the freezing of water; severe cold or
freezing weather.

The third bay comes a frost, a killing frost.
--Shak.

3. Frozen dew; -- called also {hoarfrost} or {white frost}.

He scattereth the hoarfrost like ashes. --Ps.
cxlvii. 16.

4. Coldness or insensibility; severity or rigidity of
character. [R.]

It was of those moments of intense feeling when the
frost of the Scottish people melts like a snow
wreath. --Sir W.
Scott.

{Black frost}, cold so intense as to freeze vegetation and
cause it to turn black, without the formation of
hoarfrost.

{Frost bearer} (Physics), a philosophical instrument
illustrating the freezing of water in a vacuum; a
cryophorus.

{Frost grape} (Bot.), an American grape, with very small,
acid berries.

{Frost lamp}, a lamp placed below the oil tube of an Argand
lamp to keep the oil limpid on cold nights; -- used
especially in lighthouses. --Knight.

{Frost nail}, a nail with a sharp head driven into a horse's
shoe to keep him from slipping.

{Frost smoke}, an appearance resembling smoke, caused by
congelation of vapor in the atmosphere in time of severe
cold.

The brig and the ice round her are covered by a
strange black
obscurity: it is the frost smoke of arctic winters.
--Kane.

{Frost valve}, a valve to drain the portion of a pipe,
hydrant, pump, etc., where water would be liable to
freeze.

{Jack Frost}, a popular personification of frost.